Will cancer vaccine get to all women?

[Guest guest]

Will cancer vaccine get to all women?

16 April 2005

NewScientist.com news service

Debora MacKenzie

 

DEATHS from cervical cancer could jump fourfold to a million a year by 2050,

mainly in developing countries. This could be prevented by soon-to-be-approved

vaccines against the virus that causes most cases of cervical cancer - but there

are signs that opposition to the vaccines might lead to many preventable deaths.

 

The trouble is that the human papilloma virus (HPV) is sexually transmitted. So

to prevent infection, girls will have to be vaccinated before they become

sexually active, which could be a problem in many countries.

 

In the US, for instance, religious groups are gearing up to oppose vaccination,

despite a survey showing 80 per cent of parents favour vaccinating their

daughters. " Abstinence is the best way to prevent HPV, " says Bridget Maher of

the Family Research Council, a leading Christian lobby group that has made much

of the fact that, because it can spread by skin contact, condoms are not as

effective against HPV as they are against other viruses such as HIV.

 

" Giving the HPV vaccine to young women could be potentially harmful, because

they may see it as a licence to engage in premarital sex, " Maher claims, though

it is arguable how many young women have even heard of the virus.

 

Meanwhile in developing countries, where 80 per cent of deaths from cervical

cancer occur, social taboos may be even more powerful. The head of the Indian

Council of Medical Research, N. K. Ganguly, says it will take a big educational

effort to convince parents. Vaccinating men could be the best way to prevent the

spread of HPV among women.

 

HPV is extremely common. Half of all sexually active women between 18 and 22 in

the US are infected. Most cases clear up, but sometimes infection persists and

can cause cancer decades later.

 

Deaths in the west have plummeted thanks to widespread screening to detect

cancers early. But such screening is not widely available in developing

countries. In many, populations are ageing: in India the number of women over 60

is projected to rise from 40 million now to 168 million in 2050. The

International Agency for Research on Cancer in Lyon, France, calculates that by

then deaths from cervical cancer will reach a million a year in poor countries

if rates of infection, and of cancer detection and treatment, do not improve.

 

While vaccination could slash infection rates, its cancer-preventing benefits

will not be evident for decades, as it will take that long for vaccinated girls

to reach an age when they might otherwise have developed cancer. Meanwhile,

millions of women who are already infected must be screened and treated. If

there is widespread resistance to vaccination, it will take even longer for its

benefits to become clear.

 

Vaccines are producing good results in clinical trials, and the first could be

licensed as early as next year. GlaxoSmithKline announced in November 2004 that

its vaccine, which contains two strains of HPV thought to cause 70 per cent of

cervical cancers, had prevented 90 per cent of new infections and all persistent

infections. The US-based firm Merck announced similar results last week with its

vaccine, which contains the same two cancer-causing HPV strains plus two strains

that cause genital warts.

 

Merck's official reason for including the warts strains is that they can confuse

screening tests, leading to unnecessary scares. But another reason, says Anne

Szarewski of the charity Cancer Research UK, who is helping to organise one of

the vaccine trials, is that men who get vaccinated to prevent disfiguring warts

will no longer transmit the cancer-causing strains to women. That might be the

key to getting vaccines accepted in cultures where trying to prevent sexually

transmitted infections is equated with promiscuity.

 

" We found that some Asian women in Britain are afraid even to get tested for HPV

infection, because they say if it is positive they will be killed, never mind

that their husbands probably gave it to them, " says Szarewski. She feels that

such attitudes may mean that HPV vaccination may be a non-starter in such

communities.

 

Greg Zimet of Indiana University in Indianapolis is more optimistic. His surveys

in the US show parents overwhelmingly favour getting their daughters vaccinated.

" Doctors tend to fear the worst, " he says.

 

But some problems have already surfaced. India is planning to do its own

clinical trials, but will not test the vaccine in young girls. " This is not

possible until around the age of marriage in India, " Ganguly says.

 

Once licensed, the vaccine should be given to younger girls, he says. " But

people will say 'My girl is very virtuous, why vaccinate?' It will be a real

challenge, not like other vaccines. "

 

Last but not least is the cost. Ganguly is trying to arrange for an HPV vaccine

to be produced cheaply in India. But there are fears India's new patent laws

will make licensing deals difficult.

Related Articles

Gel may help cure cervical cancer

http://www.newscientist.com/article.ns?id=dn6704

26 November 2004

Coming soon: the first cancer vaccines

http://www.newscientist.com/article.ns?id=mg18424742.100

20 November 2004

Vaccine may protect against cervical cancer

http://www.newscientist.com/article.ns?id=dn6662

12 November 2004

 

Weblinks

Bridget Maher, Family Research Council

http://www.frc.org/ie/bios.html

Indian Council of Medical Research

http://icmr.nic.in/

Cancer Research UK

http://www.cancerresearchuk.org/

 

 

 

 

http://www.blueaction.org

A politician is a man who will double cross that bridge when he comes to it

http://babyseals.care2.com/